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Home , Ardea (bird), Egret, Great egret, Heron

Herons and — Family Ardeidae 131

Great alba Decimated in southern California at the beginning of the 20th century, the has enjoyed a recovery that is still continuing. In San Diego County it was long a nonbreeding visitor only, mainly in fall and winter, and it is still most numer- ous in that role. The first known nesting was in 1988, and more colonies formed soon thereafter, until by the arrival of the 21st century the county’s breeding population numbered about 75 pairs, most at the Wild Park and Rancho Santa Fe. But the establishment of new colonies, often mixed with those of other , continued past the end of the atlas period in 2002. Breeding distribution: The primary Great Egret colony in San Diego County, founded in 1989, is in the Wild Animal Park (J12), in the multispecies colony of herons Photo by Anthony Mercieca and in the Heart of exhibit. Counts here range up to 100 on 15 June 1998 (D. and D. Bylin) and 40 nests on 9 May 1999 (K. L. Weaver). The colony in Great Egret, near two of the Great Blue , had two Rancho Santa Fe (L8), in trees within a private nearly full-grown nestlings (P. Unitt). In the Great Blue estate along Escondido Creek near La Bajada, is second Heron colony at the Point Loma navy research laboratory in size. In 1998, the first year in which the egret nested (S7), one pair of the Great Egret nested in 2000 but failed. there in numbers, there were 25 to 30 nests, with a similar In 2002, however, two pairs nested at this site, one suc- number of nests (A. Mauro). cessfully, and in 2003 three pairs nested, all successfully The other colonies established themselves after the (M. F. Platter-Rieger). atlas period began in 1997. At El Capitan Reservoir Yet another new colony formed in 2000 was at the east (O16), nesting began in 2000 with a single pair with end of Lake Wohlford (H12), with six birds on 28 May (P. nestlings 21 June (D. C. Seals). The next year, on 9 July, Hernandez, S. Christiansen, E. C. Hall). On 20 May 2001, one eucalyptus tree overlooking the lake contained three the colony appeared to be growing rapidly, with 35 individ- nests of the Great Egret, two of the Snowy, and one of uals in courtship displays and nest building and incubation the Great Blue Heron (J. R. Barth, R. T. Patton, P. Unitt). apparently begun in one nest. Less than seven weeks later, At Lindo Lake, Lakeside (P14), Great Egret nesting also however, on 7 July, the colony had been deserted and not a began in 2000, with one carrying nest material 18 May single egret remained in the area (P. Unitt). (M. B. Stowe). On 9 July 2001, there were five nests of the The establishment of new colonies continued after Great Egret, among more of the Great Blue Heron, Snowy the atlas period with three nests of the Great Egret on Egret, and Black-crowned Night-Heron (J. R. Barth, R. T. the north side of Batiquitos Lagoon (J7) in 2003 (R. Patton, P. Unitt). On 11 August 2001, on the south side Ebersol). of the San Dieguito River estuary (M7), one nest of the Away from breeding colonies, the Great Egret is wide- 132 Herons and Bitterns — Family Ardeidae

Nesting: Like the Great Blue Heron, the Great Egret builds a platform of sticks high in trees. In the mixed colony at Rancho Santa Fe, the Great Blue’s nests were higher, above the egrets’. At most sites in San Diego County, the nests are in euca- lyptus, but at the San Dieguito River mouth and Point Loma the birds were in Torrey pines; at Lake Wohlford they were in coast live oaks. The schedule of Great Egret nesting in San Diego County is variable. In 1998, egg laying in the Rancho Santa Fe colony had apparently begun by late February; a search underneath the colony on 5 March yielded some broken eggs fallen to the ground (A. Mauro). By 11 May some young from this colony spread at both coastal and inland . Some of the larger concentrations, up to 75 at Lake Hodges 14 June 1999 (R. L. Barber) and 61 at San Elijo Lagoon 10 July 1999 (P. A. Ginsburg), were probably of birds commuting from or recently fledged from nearby colonies. But others, such as 16 at O’Neill Lake (E6) 9 June 1998 (P. A. Ginsburg), 33 at Batiquitos Lagoon 3 April 1998 (F. Hall, C. C. Gorman), and 18 at Los Peñasquitos Lagoon (N7) 3 April 1999 (K. Estey) were not—though they suggest sites for future colonies. In the mountains the Great Egret is rare during the breeding season, with reports of no more than two (at Wynola, J19, 17 April–2 July 1999, S. E. Smith; near Julian, K20, 10 June 1998, E. C. Hall). had already fledged while others were still downy. At Point Loma the young hatched in May and June (M. F. Platter-Rieger). The large nest- lings at the San Dieguito River mouth 11 August 2001 must have hatched from eggs laid in early June. Migration: Although the Great Egret has colonized San Diego County as a nesting , its primary role is still that of a nonbreeding visitor. Censuses around San Diego Bay show the egret’s numbers peaking from November to February and reaching their nadir in June, with gradual changes in between. Around north San Diego Bay, Mock et al. (1994) had their high count of 88 on 9 November 1994; in the salt works, Stadtlander and Konecny (1994) had their high count of 83 on 17 November 1993. Postbreeding dispersal to Herons and Bitterns — Family Ardeidae 133 higher elevations is underway by August, with up to ten at Conservation: The Great Egret was decimated in south- Cuyamaca Lake (M20) 10 August 1998 (J. R. Barth). ern California around 1900, when the birds were killed for In and near the Anza–Borrego Desert, the Great Egret their plumes, in fashion for decorating ladies’ hats. Once occurs primarily as a rare migrant, recorded in fall as this trade was suppressed, recovery began. In the winter of early as 21 July (1994, three at the Roadrunner Club, 1912–13, Grey (1913b) reported up to 20 at the south end Borrego Springs, F24, M. L. Gabel), in spring as late as 6 of San Diego Bay 25 December; previously, he had seen no May (1999, one at Banner, K21, P. K. Nelson). Generally more than four. By 1936, a large roost had formed at Point the species is seen singly; exceptional concentrations Loma, with a maximum of “well over 150” on 25 February are of ten at the Borrego Springs sewage pond (H25) (Sefton 1936). The population began another upsurge 10 October 1992 (A. G. Morley) and seven in the north in the late 1970s. King et al. (1987) noted an increase at Borrego Valley (E24) 6 May 2000 (P. D. Ache). Most San Elijo Lagoon from 1973 to 1983. From 1960 to 1977 desert records are from the Borrego Valley, but a few are the San Diego Christmas count averaged 26.5 Great from scattered localities far from suitable habitat, such as Egrets; from 1997 to 2001 it averaged 106.4. Ocotillo Wells (I28; two on 1 April 2000, R. Miller) and Nesting began in 1988 with a pair at the Dairy Mart Canyon sin Nombre (P29; one on 29 April 2000, F. A. pond in the Tijuana River valley (V11; G. McCaskie, AB Belinsky, M. G. Mathos). 42:1339, 1988). This site soon became unsuitable, but the first nesting at the Wild Animal Park took place the fol- Winter: In the coastal lowland, wintering Great Egrets lowing year (J. Oldenettel, AB 43:1367, 1989), and by 1991 are widespread and locally common. Many of the birds the colony had grown to 30 pairs (J. O’Brien, AB 45:1160, in the Wild Animal Park remain through the winter, with 1991). up to 71 on 30 December 2000 (K. L. Weaver). Farther Herons and humanity have an uneasy relationship. inland, the Great Egret is uncommon and scattered, with People now admire the Great Egret’s beauty without hav- up to five in Ramona (K15) 30 December 2000 (D. and C. ing to wear it themselves. But heron colonies are messy Batzler) and seven at Barrett Lake (S19) 5 February 2000 affairs, unwelcome when they form over public parks like (R. and S. L. Breisch). Even as high as Cuyamaca Lake the Lindo Lake. The egrets prefer to nest near water where Great Egret is fairly regular in winter, with up to two on they can feed, so they are likely to choose sites frequented 18 February 1999 (A. P. and T. E. Keenan). by people where they are hard to ignore and vulnerable In the Anza–Borrego Desert in winter the Great Egret to disturbance. is rare, with just four records of single birds from 1997 to 2002. It has been recorded on just three of 18 Anza– : Great Egrets in the New World are A. a. Borrego Christmas bird counts 1984–2001, though the Gmelin, 1789, differing from the in the count on 20 December 1987 yielded eight. by their almost wholly yellow bills.